Great news for our seas and oceans! Here, in the UK what was the "Marine Bill" has been passed as an act! Here, begins a great future for our coastal waters and the beginning of a legal framework which will allow and support the protection of our seas and oceans.
More to follow...
Sunday, 15 November 2009
Monday, 9 November 2009
The Age of Stupid
It has been a while - apologies for the delay in confirming that yes it was a short snouted seahorse!
This December is an important month for our global environment. World leaders from 192 countries will be meeting to create a global deal on climate change. The 4 essential requirements for this international agreement are:
1.) How much are industrialised countries willing to reduce their emissions of greenhouse gases?
2.) How much are major developing countries such as China and India willing to do to limit the growth of their emissions? 3.) How is the help needed by developing countries to engage in reducing their emissions and adapting to the impacts of climate change going to be financed? 4.) How is that money going to be managed?
We are all too aware now that our climate is changing. The evidence is all around us both locally and further afield. There is an increased frequency of “freak” weather events – tornadoes, tsunamis and earthquakes appear to be a more regular occurrence. Our climate is certainly changing with wetter Summer’s and seasonal inconsistencies. It’s difficult to understand how it is changing & how to predict the change but it is changing and rapidly beyond the course of Nature’s global cycles. There are many predictions about the effects but we are sure change is afoot - there are now established organisations to reduce the impact of climate change in the UK and abroad. The Maldives are already in discussion about where their refugees will reside when the islands are gone. Indeed, estimations predict that global warming could create 150 million “climate refugees” by 2050.
Sea level is rising and our ice caps are melting. What else is the future of our seas and oceans as far as climate change goes? Well, firstly it’s important to reiterate that our atmospheric oxygen comes from trees and plankton. Scientists theorise that up to 50% of atmospheric oxygen comes from phytoplankton in our seas. It may surprise some to know that the sea acts as a great source and sink of atmospheric gases – both good and bad! As well as the contribution to the “Greenhouse Effect” the ocean absorbs more than 25% of carbon dioxide emissions. In response to this the ocean is becoming more acidic. Extreme ocean acidification could make it harder for anything that needs a shell to grow and for organisms to breathe and reproduce - some will be more sensitive than others such as giant squid and there could be economic impacts on fisheries such as the shellfish industry. Could ocean acidification affect this important powerhouse that is phytoplankton? We can’t be sure but it’s another reason to do something to minimise the impact of our wasteful ways.
On Tuesday 1st December at 7.30pm there will be a showing of, “The Age of Stupid”. This is the new four-year epic from McLibel director Franny Armstrong. Oscar-nominated Pete Postlethwaite stars as a man living alone in the devastated world of 2055, looking at old footage from 2008 and asking: why didn’t we stop climate change when we had the chance?
It’s a great film and whilst it may seem a tad heavy leading up to the Christmas period it demonstrates real glimmers of hope. There are demonstrations of how we as a global and local community are becoming far more aware, pro-active and considerate. Locally, in the South Hams we have the second highest recycling rates in England, Modbury was the first plastic bag free town our beach cleans are well attended and we should be proud and encouraged by our collective efforts. It’s not all doom and gloom! In view of the Copenhagen conference I thought it might be timely to show this film and to voice our support to the UK government for reduction in emissions. Learn To Sea is putting on this video free of charge but donations will be welcomed to cover the costs of the license and use of the village hall.
Whilst our UK representatives are making decisions about how the UK can reduce any impact of climate change, I hope that watching this film might also spurn us on to making further commitments for the future. Please do come along.
This December is an important month for our global environment. World leaders from 192 countries will be meeting to create a global deal on climate change. The 4 essential requirements for this international agreement are:
1.) How much are industrialised countries willing to reduce their emissions of greenhouse gases?
2.) How much are major developing countries such as China and India willing to do to limit the growth of their emissions? 3.) How is the help needed by developing countries to engage in reducing their emissions and adapting to the impacts of climate change going to be financed? 4.) How is that money going to be managed?
We are all too aware now that our climate is changing. The evidence is all around us both locally and further afield. There is an increased frequency of “freak” weather events – tornadoes, tsunamis and earthquakes appear to be a more regular occurrence. Our climate is certainly changing with wetter Summer’s and seasonal inconsistencies. It’s difficult to understand how it is changing & how to predict the change but it is changing and rapidly beyond the course of Nature’s global cycles. There are many predictions about the effects but we are sure change is afoot - there are now established organisations to reduce the impact of climate change in the UK and abroad. The Maldives are already in discussion about where their refugees will reside when the islands are gone. Indeed, estimations predict that global warming could create 150 million “climate refugees” by 2050.
Sea level is rising and our ice caps are melting. What else is the future of our seas and oceans as far as climate change goes? Well, firstly it’s important to reiterate that our atmospheric oxygen comes from trees and plankton. Scientists theorise that up to 50% of atmospheric oxygen comes from phytoplankton in our seas. It may surprise some to know that the sea acts as a great source and sink of atmospheric gases – both good and bad! As well as the contribution to the “Greenhouse Effect” the ocean absorbs more than 25% of carbon dioxide emissions. In response to this the ocean is becoming more acidic. Extreme ocean acidification could make it harder for anything that needs a shell to grow and for organisms to breathe and reproduce - some will be more sensitive than others such as giant squid and there could be economic impacts on fisheries such as the shellfish industry. Could ocean acidification affect this important powerhouse that is phytoplankton? We can’t be sure but it’s another reason to do something to minimise the impact of our wasteful ways.
On Tuesday 1st December at 7.30pm there will be a showing of, “The Age of Stupid”. This is the new four-year epic from McLibel director Franny Armstrong. Oscar-nominated Pete Postlethwaite stars as a man living alone in the devastated world of 2055, looking at old footage from 2008 and asking: why didn’t we stop climate change when we had the chance?
It’s a great film and whilst it may seem a tad heavy leading up to the Christmas period it demonstrates real glimmers of hope. There are demonstrations of how we as a global and local community are becoming far more aware, pro-active and considerate. Locally, in the South Hams we have the second highest recycling rates in England, Modbury was the first plastic bag free town our beach cleans are well attended and we should be proud and encouraged by our collective efforts. It’s not all doom and gloom! In view of the Copenhagen conference I thought it might be timely to show this film and to voice our support to the UK government for reduction in emissions. Learn To Sea is putting on this video free of charge but donations will be welcomed to cover the costs of the license and use of the village hall.
Whilst our UK representatives are making decisions about how the UK can reduce any impact of climate change, I hope that watching this film might also spurn us on to making further commitments for the future. Please do come along.
Monday, 7 September 2009
Seahorse Pic
I think this may be a Short Snouted Seahorse that is found in British waters - I am waiting for comfirmation. For more info on seahorses - visit www.theseahorsetrust.org
Sunday, 6 September 2009
Seahorses on the strandline
Well, if it's not Portuguese man of war it's seahorses! What an amazing Summer of discoveries. Today I was working with the British Trust of Conservation Volunteers. I was running a workshop on marine litter and we were looking on the strandline for mermaids tears / plastic pellets (I'll explain in a later blog) when I discovered a small dried seahorse. Seahorses keep their shape amazingly when they die due to their bony plates. Sadly, these dried seahorses are sold in curios shops - I would ask that you do not buy these as there is a high chance they weren't found on a strandline! So not only pipefish in the pools but seahorses too...strange to discover one today after having written about them only days before on this blog! It's hard to say where it came from - it could have been washed ashore from some distance or closer to home - how exciting it would be to find a local patch!
What will get washed up next?!
What will get washed up next?!
Sunday, 23 August 2009
Seahorses & Pipefish
I've always loved seahorses - they are beautiful creatures in a wide range of colours, sizes and shapes. When I was doing my Marine Biology degree at Plymouth University my dissertation was on seahorses. I investigated the "stocking density of Knysna Seahorses". Which was much more fun than it sounds. Within China they use seahorses for Chinese medicine treatments and unfortunately many get taken from the wild for this purpose. To stop or change a cultures tradition is often impossible, naive and takes a very long time. If alternative options can be found in the short term then this is a great interim solution. So they were trying to encourage the captive breeding of seahorses in places like the Phillipines. As with any farming there is a key stocking density which ends up with lowest morbidity rates and highest fecundity rates...or in plain English the best numbers to keep animals so that you don't end up with deaths and they are happy enough to have babies.
So I had 140 baby Knysna seahorses at the National Marine Aquarium which I lovingly reared in 6 tanks with 10 in 2, 20 in 2, 40 in another 2 tanks and waited to see what happened. It meant that I had the pleasure of coming in every day to take a look in at these beautiful creatures - clean their tanks and have lovely one way conversations with them. It gave me the opportunity to watch the other resident seahorses too.
Early in the morning the paired up seahorses would start their beautiful courtship ritual and dance and flutter their fins at each other. It is one of the most beautiful spectacles to be seen. The best thing about this courtship ritual is that you know at the end that it is the male that carries the eggs full term and gives birth to the babies - hurrah!! This surely must be the most evolutionary advanced of all creatures? The female lays the eggs in the male pouch and there he fertilizes them - ensuring he is the father of his brood. Then - I have witnessed this first hand - tiny little miniature forms of the parents shoot out of the pouch into the water - a truly amazing spectacle.
So it may surprise some to know that there are not only seahorses in British waters - although hard to find and relatively rare. But their cousins, the pipefish, are found on most rocky shores although tricky to locate as they look so similar to the stems of the wrack seaweeds. But today we found several pipefish and had the opportunity to admire their snouty noses and beautiful fins oscillating in the water. There's been quite a few Learn To Sea events since the last blog and all have gone down well and as we near the end of the Summer season it is sad to think I won't be spending so much time with my intertidal friends. There has been some great feedback and I've had some very kind remarks from visitors -
"My son thoroughly enjoyed the experience -in fact this is is his 2nd go."
"I'm now converted to rockpooling"
"Well done Maya an interesting and informative talk"
and in a lovely email...
"We joined you for a rockpooling session on the 25th July and would just like to say what a wonderful time we had and how informative you were and the way you brought that knowledge across to children and adults alike.
Also whilst on this holiday the children spotted you on the news talking about the Portuguese Man of War which made them even more excited to know they had been in the presence of a real tv star, especially after your appearance on Springwatch...Thanks again for a great time and definitely will be booking up again when we are able to get away from Sussex and down to Devon"
So I had 140 baby Knysna seahorses at the National Marine Aquarium which I lovingly reared in 6 tanks with 10 in 2, 20 in 2, 40 in another 2 tanks and waited to see what happened. It meant that I had the pleasure of coming in every day to take a look in at these beautiful creatures - clean their tanks and have lovely one way conversations with them. It gave me the opportunity to watch the other resident seahorses too.
Early in the morning the paired up seahorses would start their beautiful courtship ritual and dance and flutter their fins at each other. It is one of the most beautiful spectacles to be seen. The best thing about this courtship ritual is that you know at the end that it is the male that carries the eggs full term and gives birth to the babies - hurrah!! This surely must be the most evolutionary advanced of all creatures? The female lays the eggs in the male pouch and there he fertilizes them - ensuring he is the father of his brood. Then - I have witnessed this first hand - tiny little miniature forms of the parents shoot out of the pouch into the water - a truly amazing spectacle.
So it may surprise some to know that there are not only seahorses in British waters - although hard to find and relatively rare. But their cousins, the pipefish, are found on most rocky shores although tricky to locate as they look so similar to the stems of the wrack seaweeds. But today we found several pipefish and had the opportunity to admire their snouty noses and beautiful fins oscillating in the water. There's been quite a few Learn To Sea events since the last blog and all have gone down well and as we near the end of the Summer season it is sad to think I won't be spending so much time with my intertidal friends. There has been some great feedback and I've had some very kind remarks from visitors -
"My son thoroughly enjoyed the experience -in fact this is is his 2nd go."
"I'm now converted to rockpooling"
"Well done Maya an interesting and informative talk"
and in a lovely email...
"We joined you for a rockpooling session on the 25th July and would just like to say what a wonderful time we had and how informative you were and the way you brought that knowledge across to children and adults alike.
Also whilst on this holiday the children spotted you on the news talking about the Portuguese Man of War which made them even more excited to know they had been in the presence of a real tv star, especially after your appearance on Springwatch...Thanks again for a great time and definitely will be booking up again when we are able to get away from Sussex and down to Devon"
Tuesday, 28 July 2009
Portuguese Man o' War!
Living by the coast and spending so much time on, in or by the sea you always imagine that any day soon something formidable, unusual or iconic will wash up on your shores or swim before your very eyes. Well for me today was not that day but for my daughter & husband it was! They were down by the Quay on the Avon estuary when they saw what looked like a small inflated balloon floating past. They immediately recognised it as a Portuguese Man-Of-War and somehow (I would not advise this) scooped it into a bucket. Then another family brought theirs over and they arrived home to a very shocked me with a bucket full of Portuguese Man-Of-War!
They are beautiful creatures, although we know them to be harmful and occasionally deadly. In reality they are also very stunning. Their balloon like float was a blue/purple tinged bubble with incredible spiral "springy" tentacles which boinged up and down like a coiled spring. I was completely mesmerised. You see photos of creatures such as these but in reality they are just so incredible and awe inspiring!
So what are they? Jellyfish they are not - they are in fact a great example of team work. They are a "siphonophore" and are made up of 4 individual animals with 4 individual functions that are merged to create one animal. They use their stings to prey on small fish and shrimps and catch them through paralysis. They don't, as some might imagine, have stings to purposefully set out to find naked skin and sting - it is just a highly advanced adaptation to catching prey in a mobile and aquatic environment. They use their gas filled chamber quite literally as a sail to blow their way across our oceans in great swarms. Normally, they are found in tropical and sub-tropical waters but occasionally individuals get blown off course and end up in foreign waters such as the 2 found in Bantham today.
The venom is harmful and tentacles and the animal should be avoided. If you do get contact seek immediate medical advice. At this stage there is no need to worry about them in our waters...but be aware, be careful and inform a lifeguard if you see one.
Monday, 27 July 2009
Magnificent!
What a lovely day! After a particularly wet & challenging day yesterday (despite previous post's optimism) I was greeted by blue skies this morning! I had a booking with a group that had been out the previous week and had made a repeat booking today. They were a pleasure last time and we'd had a great time rockpooling and making seaweed presses. So for an alternative I got my laptop and digital microscope out for some magnifying fun!
It worked a treat and we had a look at the underside of a cushion starfish and all the amazing suckers that run down the length of the 5 arms. The little suckers were stretching out in every direction to find a surface to adhere to and just looked incredible under magnification. The children loved it and were equally stunned when we did a mini experiment in the back of the "Van Lab".
If you take some coral weed, I had been told, and put it in some vinegar the calcareous skeleton on the outside of the coral weed would dissolve. Luckily, I had some vinegar in the van for cleaning the windows - much better than nasty chemicals - and so I put a small piece of coral weed in a small microscope tray and added the vinegar...Hey Presto!! As quick as you can say "Starfish" the weed started bubbling away which we could see so well with our laptop/microscope set up. As the calcium carbonate dissolved in the vinegar bubbles of carbon dioxide appeared and the stony skeleton simply dissolved away to leave some naked, filamentous seaweed. I'm not sure who was more excited the children or me! Either way it was great to see some real science under the microscope and have children so engrossed. Science is so much fun when it's hands on and children can directly experience science before their very eyes! It makes it all so worthwhile to see children having so much fun and learning at the same time.
So there will definitely be more "experiments" in the Van-Lab after today's magnificent day!
It worked a treat and we had a look at the underside of a cushion starfish and all the amazing suckers that run down the length of the 5 arms. The little suckers were stretching out in every direction to find a surface to adhere to and just looked incredible under magnification. The children loved it and were equally stunned when we did a mini experiment in the back of the "Van Lab".
If you take some coral weed, I had been told, and put it in some vinegar the calcareous skeleton on the outside of the coral weed would dissolve. Luckily, I had some vinegar in the van for cleaning the windows - much better than nasty chemicals - and so I put a small piece of coral weed in a small microscope tray and added the vinegar...Hey Presto!! As quick as you can say "Starfish" the weed started bubbling away which we could see so well with our laptop/microscope set up. As the calcium carbonate dissolved in the vinegar bubbles of carbon dioxide appeared and the stony skeleton simply dissolved away to leave some naked, filamentous seaweed. I'm not sure who was more excited the children or me! Either way it was great to see some real science under the microscope and have children so engrossed. Science is so much fun when it's hands on and children can directly experience science before their very eyes! It makes it all so worthwhile to see children having so much fun and learning at the same time.
So there will definitely be more "experiments" in the Van-Lab after today's magnificent day!
Tuesday, 21 July 2009
Rockpools "made a dreary day fun!"
So today was pretty wet as far as Summer days go (compared to 2007 anyhow!!). I have to admit I woke up to the sound of rain and and just felt a bit let down! Rockpool ramble trips are under full swing at South Milton Sands now the holiday season has started and Learn To Sea is fully booked every day until next Monday come rain or shine!!
Well, I donned my (usually Winter) waterproofs and marched off to South Milton to face the music! I was greeted by a lovely family who were due to come out with me on a guided rockpool tour. Luckily, they came prepared and with a great British constitution of sheer stubborn mindedness in the face of rubbish weather. So, off we trotted...There are drawbacks to wet days rockpooling. Where we would normally head to the stone arch - it proves too difficult and slippery on a wet / windy day. So we ventured to a different more flat area of rocks.
Luckily, I knew from previous experience that while we wouldn't find some of the more unusual finds at the stone arch we would see some real gems. But it was one of the best rockpooling trips in a long while! Lots of starfish, netted whelks and many other creatures to show the families. They were beautiful rockpools that ran the length of the bedrock to the sea which were teaming with colour and life. We were so engulfed in our explorations that we completely forgot about the rain! The fact that the day was so wet made it seem even more exhilarating to be out exploring regardless of weather conditions.
I'm so glad that all the visitors are such hardy creatures and have good waterproofs! While we may hesitate at the thought of going out on a wet day - the rockpool creatures are still there to be found. We still managed to make some lovely seaweed presses and avoided any terrible daytime television or thumb twiddling.
The feedback form for the day said "Maya made a dreary day fun!" I would agree we had fun but I just facilitated it - it was the rockpools and good company which made it so much fun. I, for one, am looking forward to some more rainy days out rockpooling... although I wouldn't complain if it was sunny too!!
Well, I donned my (usually Winter) waterproofs and marched off to South Milton to face the music! I was greeted by a lovely family who were due to come out with me on a guided rockpool tour. Luckily, they came prepared and with a great British constitution of sheer stubborn mindedness in the face of rubbish weather. So, off we trotted...There are drawbacks to wet days rockpooling. Where we would normally head to the stone arch - it proves too difficult and slippery on a wet / windy day. So we ventured to a different more flat area of rocks.
Luckily, I knew from previous experience that while we wouldn't find some of the more unusual finds at the stone arch we would see some real gems. But it was one of the best rockpooling trips in a long while! Lots of starfish, netted whelks and many other creatures to show the families. They were beautiful rockpools that ran the length of the bedrock to the sea which were teaming with colour and life. We were so engulfed in our explorations that we completely forgot about the rain! The fact that the day was so wet made it seem even more exhilarating to be out exploring regardless of weather conditions.
I'm so glad that all the visitors are such hardy creatures and have good waterproofs! While we may hesitate at the thought of going out on a wet day - the rockpool creatures are still there to be found. We still managed to make some lovely seaweed presses and avoided any terrible daytime television or thumb twiddling.
The feedback form for the day said "Maya made a dreary day fun!" I would agree we had fun but I just facilitated it - it was the rockpools and good company which made it so much fun. I, for one, am looking forward to some more rainy days out rockpooling... although I wouldn't complain if it was sunny too!!
Wednesday, 8 July 2009
BBC Springwatch
http://www.bbc.co.uk/blogs/springwatch/2009/05/at_the_beach.html
For those that may have missed it - here's a clip of the Springwatch piece shown in May and June this year...it was so much fun to do. I really enjoyed working with the Beeb and they were so friendly and fun to spend the day with! It's also great to see that there is so much interest in the media world of all creatures small and marine. It seems as if people are really getting back into British wildlife. There's so much to see and do on our shore and such a wonderful variety of coast to visit. Naturally, none better than South Milton Sands of course!
I've got antique Sea-shore guides and seaweed press books going back to 1880 and it's great to see people get back into doing things our forefathers and mothers(!) did before us - like the wonderful seaweed presses. One obvious improvement in the way we act on the shore is our adoption of the "Seashore Code". In the "old days" they would say to "collect more rare specimens for your aquarium tanks"(!) - now we say "Leave only footprints, take only photos." It appears that perhaps we have learnt some valued lessons about conserving our intertidal creatures but not lost some age old brilliant games and activities! for more information about the "Seashore Code" check out the website - http://www.learntosea.co.uk/
For those that may have missed it - here's a clip of the Springwatch piece shown in May and June this year...it was so much fun to do. I really enjoyed working with the Beeb and they were so friendly and fun to spend the day with! It's also great to see that there is so much interest in the media world of all creatures small and marine. It seems as if people are really getting back into British wildlife. There's so much to see and do on our shore and such a wonderful variety of coast to visit. Naturally, none better than South Milton Sands of course!
I've got antique Sea-shore guides and seaweed press books going back to 1880 and it's great to see people get back into doing things our forefathers and mothers(!) did before us - like the wonderful seaweed presses. One obvious improvement in the way we act on the shore is our adoption of the "Seashore Code". In the "old days" they would say to "collect more rare specimens for your aquarium tanks"(!) - now we say "Leave only footprints, take only photos." It appears that perhaps we have learnt some valued lessons about conserving our intertidal creatures but not lost some age old brilliant games and activities! for more information about the "Seashore Code" check out the website - http://www.learntosea.co.uk/
Barnacle Bill!
Our intertidal zone, where the land meets the sea, is an area that has always intrigued and fascinated me. The thing that never ceases to amaze me is that the more you know about life in the rockpools the more intriguing and incredible it is. Even the most ordinary looking creature is extraordinary through its habits, feeding mechanisms and reproduction. They live in such a harsh environment – what we experience seasonally in a year – they endure in 12 hours. In one tidal cycle they have to survive extreme conditions. They go from being below the waves in a fairly constant cool temperature and salinity to having the tide dropping and, on a Summers day, the water in the pools heating up rapidly. The salinity increases as water evaporates and the amount of oxygen in the water drops as does the amount of food around them. Conversely, they have an increased pressure of predation in this now smaller environment. The tide rises and they have the fear of the waves smashing their bodies against the rocks. It is this unique and stressful environment which leads to some of the incredible habits and body shapes and structures of our intertidal creatures.
I love dolphins as much as the next person and if anybody asks what their favourite marine creature is many will say – dolphins, whales and seals. These are our iconic sea mammals and we feel a sort of spiritual connection with these intelligent and expressive animals. It’s a shame that there is not more coverage of some of the smaller creatures that may not have the expressive eyes and acrobatic skills but are none the less amazing animals. Let’s take a look at the barnacle for example. Barnacles are really quite incredible creatures that many people may curse when they walk over the rocks because of their sharp volcanic homes that they create.
Barnacles have an incredible life cycle - relatives of the crabs, lobsters and prawns they are classified as “Cirripedia” and Darwin did much to clarify the classification, different body shapes and various life cycles of the lowly and numerous barnacle species. He was the one to point out that they were not molluscs like mussels, periwinkles and other bivalves but actually crustaceans.
They start off life as much of our marine intertidal animals do as a larval stage – but not just as one but two stages. It starts off as a “naupilus” a free swimming, one eyed planktonic creature. After several moults (just like a crab moults) it develops into the next more complex stage which is called a “cyprid” and here they search out a place to call home. They use structures called antennules, like antenna, to find a good spot to settle for the rest of its sedentary life. Once it’s found the perfect spot it cements itself to the rock with its head...very strange behaviour. Once attached the cyprid then creates a sturdy, rocky, volcanic looking home around its delicate body – this takes about 12 hours. Now, it looks like the barnacle that we all know.
Once settled, it starts its cyclical feeding on the high tide. Cirripedes means “curl footed” in Latin and it is this apparatus that it uses to scoop out tiny bits of food from the water. On the low tide to protect itself from predators it closes a trapdoor and rests in its own cool pool of water as the tide drops. But if it’s stationary how does it reproduce with its neighbour? Well, this is another fascinating area of the barnacle life cycle – with a long (largest relative to body size in the animal kingdom) extendable phallus the barnacle searches for a neighbouring female and fertilizes her externally. Once this has taken place the phallus then falls off! Once the fertilized eggs are “hatched” into the naupilus larvae they are released into the water column and so the life cycle begins again...amazing stuff! You might have thought the different life stages of a frog were amazing but what about that for a life cycle! So, this Summer next time you look at a barnacle take a minute to think about the extraordinary lengths it has gone to to get where it is!
So, there we have it - a seemingly insignificant creature that has got to be respected for its incredible life cycle and fight against the odds for survival in this harsh and intertidal zone.
I love dolphins as much as the next person and if anybody asks what their favourite marine creature is many will say – dolphins, whales and seals. These are our iconic sea mammals and we feel a sort of spiritual connection with these intelligent and expressive animals. It’s a shame that there is not more coverage of some of the smaller creatures that may not have the expressive eyes and acrobatic skills but are none the less amazing animals. Let’s take a look at the barnacle for example. Barnacles are really quite incredible creatures that many people may curse when they walk over the rocks because of their sharp volcanic homes that they create.
Barnacles have an incredible life cycle - relatives of the crabs, lobsters and prawns they are classified as “Cirripedia” and Darwin did much to clarify the classification, different body shapes and various life cycles of the lowly and numerous barnacle species. He was the one to point out that they were not molluscs like mussels, periwinkles and other bivalves but actually crustaceans.
They start off life as much of our marine intertidal animals do as a larval stage – but not just as one but two stages. It starts off as a “naupilus” a free swimming, one eyed planktonic creature. After several moults (just like a crab moults) it develops into the next more complex stage which is called a “cyprid” and here they search out a place to call home. They use structures called antennules, like antenna, to find a good spot to settle for the rest of its sedentary life. Once it’s found the perfect spot it cements itself to the rock with its head...very strange behaviour. Once attached the cyprid then creates a sturdy, rocky, volcanic looking home around its delicate body – this takes about 12 hours. Now, it looks like the barnacle that we all know.
Once settled, it starts its cyclical feeding on the high tide. Cirripedes means “curl footed” in Latin and it is this apparatus that it uses to scoop out tiny bits of food from the water. On the low tide to protect itself from predators it closes a trapdoor and rests in its own cool pool of water as the tide drops. But if it’s stationary how does it reproduce with its neighbour? Well, this is another fascinating area of the barnacle life cycle – with a long (largest relative to body size in the animal kingdom) extendable phallus the barnacle searches for a neighbouring female and fertilizes her externally. Once this has taken place the phallus then falls off! Once the fertilized eggs are “hatched” into the naupilus larvae they are released into the water column and so the life cycle begins again...amazing stuff! You might have thought the different life stages of a frog were amazing but what about that for a life cycle! So, this Summer next time you look at a barnacle take a minute to think about the extraordinary lengths it has gone to to get where it is!
So, there we have it - a seemingly insignificant creature that has got to be respected for its incredible life cycle and fight against the odds for survival in this harsh and intertidal zone.
And in the beginning there was...
Welcome to Learn To Sea's new blog site - here I will post any new info about what has been seen rockpooling lately...what Learn To Sea is up to and any thoughts for the day on marine issues.
Hope you enjoy!
Hope you enjoy!
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